S. Uellner, and V. Wulff. Physika, Heidelberg, (2000)Proceedings der ersten Tagung Computergest�tztes kollaboratives
Lernen --- D-CSCL am 23.--24. M�rz 2000.
G. Stahl. Computer Support for Collaborative Learning: Foundations for a CSCL
Community. Procedings of CSCL 2002, Boulder USA, Jan. 7--11, Lawrence Erlbaum Associates, Hillsdale, USA, (2002)